Telephone system



, Nov. 30 192s. 1,608,629

J. L. SLA' I'TERY TELEPHONE SYSTEM Filed Jan. 17. 1925 ,4 Sheets-Sheet 1 INVENTDR J.LE|3 ELA r'rERv Nov. 30 1926. 1,608,629

J. L. SLATTERY TELEPHONE SYSTEM Filed Jan. 1'7. 1925 4 Sheets-Sheet 2 INVENTDR J LEE] ELATTERY J. L. SLATTERY TELEPHONE SYSTEM Filed Jan.' 17. 1925 4 Sheets-Sheet 3 Phr INVENTD R SLATTEg Nov. 30 1926.

J.L.$LATTERY TELEPHONE SYSTEM Filed Jan. 17. 1925 4 Sheets-Sheet 4 I INVENTDR' J.LEu ELATTERY Patented Nov. 30, 1926.

stares JAMES LEO SLATTERY, OF MERRITTON, ONTARIO, CANADA.

TELEPHONE SYSTEM.

Application filed January 17, 1925. {serial No. 3,068.

This invention relates to improvements in telephone systems and particularly to the ringing circuit of telephones installed in rural districts, the main object being to pro vide a rural system of telephones wherein one station can be called without the necessity of ringing all the stations on the line, and using but the line wires already 1n service. i

This constant and annoying ringing all over the line is easily overcome with my invention, which will be clearly understood by following the description with its appended drawings, and in which- '1 Figure 1 is a faceview of a telephone ringing box arranged as per i'ny invention;

Figure 2 is a face view thereof. with the cover removed showing the operating mechanism; T

Figure 3 is a centralvertical cross section of the telephone ringing box;

' Figure 4: is an illustrationiof the electricallv operated selector;

Figure 5 shows a modified form of com- 25 mutator for the bell circuit;

Figure 6 is a diagram showing the basic principle of the selective ringing;

Figure 7c is a very simple circuit as per my invention without transformer;

Figure 8 a diagram of the selector circuit with transformer;

Figure 9 is a diagram showing the use of the main line wires for the ringing circuit; and y i l Figure 10 is a, diagram showing three complete stations with relays.

Similar characters of reference and similar electrical symbols refer to similar cor responding parts throughout the drawings.

The basic principle.

tare liar-11115,: pawl adapted to i move to 3, and so on.

is, therefore, evi

dent that by placing pointer 15 on a contact of any number will bring pointer 21 to a similar number providing pointer 15 is always rotated in a clockwise direction.

In my system,

each number indicated by pointer 15 represents the number of one station, there being as many numbers as there are stations on the line, and the numbers indicated by pointer 21. are substituted by contacts, there being only one at each station,for instance, station six will have a contact in position 6 so that when station six is called, the ringing current will pass through the said contact to the bells.

The apparatus.

The apparatus will vary in design and in its component parts according to the circuit employed. The main operating parts will, however, remain the same and in order that the diagrams of the different circuits may be more readily followed, a preferred arrangement of the apparatus as shown in Fi 1 to 1 is here describe gures In the present case, the apparatus shown can be attached to an ordinary telephone, the magneto and the bells already in the telephone being adaptable to my circuit and becoming part thereof.

For compactness, a metal box 22 provided with brackets 23 for its support is used and is fitted with a cover24. In this apparatus the series of contacts and the ratchet wheel 20 or the selecting part and the selected part as shown in Figure 6 are combined into one purpose of selecting and serves the double the wanted station when calling and placing the bell in circuit when being called.

That part of the apparatus which pertion forms the above func termed the sol s will hereinafter main ratchet wheel having a long hub 26 ending with ratchet teeth 27. Selector wheel 25 rotates on a tubular bearing 28 riveted to a bracket 29 held rigidly to the back of the box by screws 30. Inside the tubular bearing 28 is mounted an operating shaft 31 and through this shaft is fitted a pin 32 for engagement with ratchet teeth 27. On the outer end of shaft 31 is mounted a knob 33 for its manual operation. Shaft 31 is free to slide in bearing 28 and is provided at its inner end with a piece of insulating material 34 resting against the middle 51 ring 35 of a two-point switch composed of three leaf springs,35, 36 and 37. It will be seen that, due to action of spring 35, shaft 31 is pressed outwardly but prevented from further movement by pin 38 resting against bracket 29.

fit)

It will also be seen that in this position the pin 32 will not engage the ratchet teeth 27 unless pressure is applied on knob 33, which action will operate switch spring 35 for a purpose explained later on.

' The selector contact maker consists of a standard 39 insulated from the box on which is mounted contact lever 40, to which is riveted contact spring 41. In order to give rigidity to spring 41, the same is bent down and held by bending over the end of lever 40, as shown at 42. A small lug 43 on lever 40 serves to be lifted by the ratchet teeth of wheel 25, and makes contact between contact spring 41 and contact 44 adjustably mounted on a standard 45 as shown, said standard being fastened to,.but insulated from, the box. "The standard 39 is provided with two arms, each having adjusting screws 46 and lock nuts 47 for the adjust ment of contact lever 40.

The electrical operating means of the selector comprise a pair of electromagnets 48 mounted on the lower side of the box, the insulating ends 49 and 50 of the coils being continuous and perforated at 51 and 52, as shown in Figure 3, to form guides for the stem 53 of the armature 54. The armature is normally heldin a raised position by means of a spring '55 which rests on end 50 of the magnets and presses under pin 56 on the stem 53. The armature 54 is provided with two pivotally mounted pawls aS shown,pawl 57 of curved shape to engage under the teeth of wheel 25 and pawl 58 of book shape to engage over the teeth of the said wheel. The pawls are held in engagement with the teeth by means of a common springs 59 as shown. By using two pawls arranged as above described, the armature will respond more quickly as it is required to move but one half the distance as compared with the use of one ordinary pawl. This is more clearly shown in Figure 4 where the armature is lowered equal to one half the pitch of one tooth and has rotated wheel 25 accordingly by means of pawl 58. At this point, pawl 57 engages under a tooth and will impart to the wheel 25 the other half of the pitch of the tooth when the armature returns to its normal position.

This arrangement also eliminates the use of a check pawl.

The bell commutator consists of two spring contact bands 60 and 61 mounted on but insulated from a bracket 62 fastened to the back of the box as shown. Contact between the two bands is caused by a small cam 63 made of insulating material and mounted as shown in hub 26 of wheel :25 by pressingon the upper band 60. This method of contact, while suitable in a system of a few stations, will be obsolete in a system of a large number of stations owing to the small'angle of rotation of the hub between two stations. vised a means as shown in Figure 5, which consists of an insulation disc 64 having an integral hub 65 to fit over hub 26 of wheel 25. The disc 64 has a small metal section 66 embedded on its circumference which makes connection as shown with a'contact ring 67 mounted on hub 65. In this case the same bands 60 and 61 may be used, one comresting on the circumference of the disc, coming in contact with the metal section 66 as required.

On, the cover 24 appears a set of numbers placed at equal intervals, as shown, there being as many as there are teeth in wheel25 and therefore as many as there are stations on the line or of the maximum capacity of the system. The number of the station called is indicated by a pointer 68 mounted on hub 26 and although tightly fitted on same, can be forced around for adjustment. This pointer serves the same purpose as pointers 15 and 21 in diagram 6, one only being required since, as previously eX- plained, both pointers always indicate the sam number,

The instrument box also contains a con; denser 69 and a transformer 70 and the necessary connecting posts 71 to 75 included, as shown. I

The operation of this apparatus will be considered in the following paragraph covering its contained circuits.

System with transformer.

The apparatus just described operates as per system shown in diagram A, Figure 8. It will be noted that numerals in the. diagram have been made, as far as possible, identical to corresponding parts in the apparatus and'that one diagram serves to illustrate both the calling and the called stations.

Assuming that the station illustrated desires to call station number six, the operator will proceed by pressing knob 33, which will engage the wheel 25 and turn same in a For this reason, I have do mg in contact with thering 67 and the other Inc clockwise direction until pointer 68 points at number 6 on the dial. This will cause live teeth of the ratchet wheel to pass under lever 40 and will therefore make five separate connections between spring 41 and contact 44, and in the meantime connect switch spring with spring 37. At each connection, current will'flow from battery B through terminal B to spring 41, through contact 44L to switch spring 35, through spring 3'? to primary T, in transformer, and from transformer to battery through post B When the current is interrupted by lever dropping over the edge of the tooth, induction follows into the secondary T of the transformer, and from there to the two line wires, through which five impulses of current of high voltage will be transmitted. The condenser is intended to intensify the induction.

Assuming now that the station shown is the called station, five current impulses will reach it, the current flowing from L to switch spring 35 through switch spring 36 to the electromagnet and back to L It will, therefore, be seen that the armature 5% will act five times and turn pointer to (3, all stations now being turned to 6, but that particular station which is known as number six and which is being called will be adjusted so as to connect its bell circuit at that point and this is done as shown in Figure 2. The magneto of the calling sta tion now operated will cause a flow of currents between the ground and line L which at the called station will come in at L to contact band through band 61, through bells G and back to the ground. Since only station six is adjusted to make contact between bands 60 and 61 when the pointer indicates number 6, it. is evident that only this station on the line will ring, the same result applying to other stations when called.

Zlfcmnc of disconnecting transformer secondary.

It will be observed in diagram A, Figure 8, that the transformer secondary T remains in the circuit when the station is called. This is somewhat detrimental to the efficiency of the apparatus since it will provide a path for and absorb part of the current intended for the electromagnet. This is overcome by an additional contact 76 in the switch, as shown in diagram B. This will close the transformer circuit with the main line when the station is calling by coming into contact with switch bar 35 and open the same when the station is not used or being called by springing out of contact from bars 35 and 37.

3 Lip the system is to be used to establish communication between different parts and Station IV silent.

of a building or between adjoining buildings where the resistance of the line is small, the system can be simplified by the use of lower voltage by dispensing with the transformer and reducing the ohmic resistance of the selector electrolnagnets. Such a system is shown in Figure 7. In this case,the current comes in at L goes to the switch spring 35 through switch spring 36, through the electromagnet 48, and back to line L the bell circuit operating through a ground as shown or through third wire, as desired. Ywhen the station calls, current from battery passes through contacts tl and 4% to L and back from the line L to springs 35 and 3'? to the battery.

System with rcZa-y.

On the average party line of telephones, the distance between each station is fairly long, resulting in a system of fairly high resistance. This requires more sensitive in struments and consequently, besides the use of the transformer for raising the voltage in transi'nitting, I use a relay of a large number of ohms for receiving, andthe selector magnets, which are of lower ohmic resistance, are operated by means of a low voltage battery.

This system is clearly shown in Figure 10, illustrating three complete stations (I, III, and IV), including transmitter and receiver, Station I being called, Station III calling, It will be noted that the system is much the same as system with transformer described except for the addition of the relay R operating the selector circuit, and of the battery BB. Although three stations are shown, four. could be included in the line since the selector wheel has four teeth. Station II is not shown. The cam 63 will, therefore, be in aditlerent posi tion in each station. Assuming that Station I is called and'is readyfor ringing, its cam 63 will make contact between the two bands 60 and 61. It will be seen that the bell circuit of the other stations is opened and that before the said circuits are closed, selector in Number III station will act twice and in Number IV three times. The relay is connected to the line L and L as shown and is operated by the transformer current from the calling station, while the selector is operated by current from battery BB when the relay closes the circuit.

Here it will be stated that the relay can also be employed without the use of a tranc former in order to obtain a more positive control of the selector armature.

Voice carrying circuit and ground system.

In all the diagrams so far described, two main line wires are used to operate the selector system, one wire and the ground be ing used for the magneto and the bell circuits. Owing to the difficulty of securing a good ground connection, I prefer to use a third line wire for the magneto and bell circuits when the distance is short enough to warrant such expense. I also know that good results are obtained by using one line wire and the ground for operating the selector and the two main wires for the bell and magneto circuit, as shown in Figure 9. The transmitter and receiver circuit indicated by TR can be connected to the main lines in either case, as shown in Figures 9 and 10, or can be connected to one line wire and the ground, as indicated by TR in Figure 9.

The above alternatives also apply to systems not using relays and not using relays and transformers, and although all diagrams show stations connected in parallel, they may be connected in series without 'departing from the spirit of my invention as claimed below.

What I claim as my invention and desire to secure by Letters Patent is 1. In a'telephone system including connecting lines, stations comprising means to effect electrical impulses in the primary of a transformer, means to intensify said impulses, the secondary of said transformer transmitting said impulses over said lines, means to receive impulses from said lines and selectively connect one line with a grounded ringing device, and grounded means to transmit current over said line to selectively operate said ringing device.

2. In a telephone system including a plurality of stations and two connectings lines therebetween, each station comprising means to effect impulses in the primary of a transformer, the secondary of said transformer transmitting said impulses over said lines, means to receive impulses from said lines and selectively connect one line with a ringing device, a third line for said ringing device,'and means between said one line and said third line to operate said ringing device of the selected station.

3. In a telephone system including connecting lines, stations comprising means to effect electrical impulses, means to step up said impulses and transmit same over said lines, means to intensify said impulses, re-

laysto receive said impulses from said lines, means dependent on said relays to selectively connect one line with a grounded ringing device, and grounded means to transmit current over said line to operate the ringing device of the selected station.

4;. In a telephone system including a plurality of stations and two connecting lines therebetween, each station comprising means to transmit electrical impulses over said' lines, means to step up said electrical impulses, relay to receive said impulses, means dependent on said relays ta selectivel cenmet one line with the ringing device of one station, and means'between said one line and said third line to operate the ringing device of the selected station.

5. In a telephone systemincluding connecting lines, stations comprising means to .transmit electrical impulses over saidlines,

lines, means'to receive impulses from said I lines and selectively connect one line with a rin in device a third line for said rin in device, means between said one line and said thlrd line to operate said ringing device of the selected station, and means to disconnect the said impulse receiving means of the calling station when its impulse transmitting means are operated.

7 In a telephone system including connecting lines, stations comprising means to effect electrical impulses in the primary of a transformer, means to intensify said impulses, the secondary of said transformer transmitting said impulses over said lines, means to receive impulses from said lines and selectively connect one line with a grounded ringing device, grounded means to transmit current over said line to selectively operate said ringing device, and means to disconnect the said impulse receiving means of the calling station when its impulse effecting means are operated.

8. In a telephone system including a plurality of stations and two connecting lines therebetwecn, each station comprising means to effect impulses in the primary of a transformer, the secondary of said transformer transmitting said impulses over said lines, means to receive impulses from said lines and selectively connect one line with a ringing device, a third line for said ringing device, means between said one line and said third line to operate said ringing device of the selected station, and means to disconnect the said impulse receiving means of-the calling station when 'its impulse effecting means are operated.

9. In a telephone system including connecting lines, stations comprising means to transmit electrical impulses over said lines, relays to receive said impulses, and means depending on said relays to selectively connect one line with a grounded ringing device, grounded means to transmit current over said line to selectively, operate said llti ringing device, and means to disconnect the said means dependent on the said relays of the calling station when its impulse transmitting means are operated.

10. In a telephone system including one line and ground, stations comprising means to transmit electrical impulses over said line and ground, relays to receive said impulses, and means depending on said relays to selectively connect said line with a ringing device, a second line for said ringing device, means to transmit current over said line and said second line to operate said ringing device selectively, and means to disconnect the said means dependent on the said relays of the calling station when its impulse transmitting means are operated.

11. In a telephone system including a plurality of stations and two connecting lines therebetween, each station comprising means to transmit electrical impulses over said lines, relays to receive said impulses, means dependent on said relays to selectively connect one line with a ringing device, a third line for said ringing device, means Between said one line and said third line to operate one of said ringing devices, being that of the selected station, and means to disconnect the said means dependent on the said relays of the calling station when its impulse transmitting means are operated.

12. In a telephone system including connecting lines, stations comprising means to effect electrical impulses, means to step up said impulses and transmit same over said lines, means to intensify said impulses, relays to receive said impulses from said lines, means dependent on said relays to selectively connect one line with a grounded ringing device, grounded means to transmit current over said line to operate the ringing device of the selected station, and means to disconnect the said relay dependent means of the calling station when its impulse effecting means are operated.

13. In a telephone system including a plurality of stations and two connecting lines therebetween, each station comprising means to transmit electrical impulses over said lines, means to step up said electrical impulses, relays to receive said impulses, means dependent on said relays to selectively con nect one line with theringing device of one station, means between said one line and said third line to operate the ringing device of the selected station, and means to disconnect the said relay dependent means of the calling station when its impulse transmitting means are operated.

14. In a telephone system including connecting lines, stations comprising means to effect electrical impulses .in the primary of a transformer, means to intensify said impulses, the secondary of said transformer transmitting said impulses over said lines,

means to receive impulses from said lines and selectively connect one line with a grounded ringing device, grounded means to transmit current over said line to selectively ope-rate said ringing device, and means to disconnect the said secondary when its impulse transmitting means are not 0perated.

15. In a telephone system including a plurality of stations and two connecting lines therehetween, each station comprising means to effect impulses in the primary of a trans former, the secondary of said transformer transmitting said impulses over said lines, means to receive impulses from said lines and selectively connect one line with a ringing device, a third line for said ringing device, means between said one line and said third line to operate said ringing device of the selected station, and means to disconnect the said secondary when the impulse effecting means are not operated.

16. In a telephone system including con necting lines, stations comprising means to effect electrical impulses, means to step up said impulses and transmit same over said lines, means to intensify said impulses, relays to receive said impulses from said lines, means dependent on said relays to selectively connect one line with a grounded ringing device, grounded means to transmit current over said line to operate the ringing device of the selected station, and means to disconnect said step-up means when the said impulse eifecting means are inoperative.

17 In a telephone system including a plurality of stations and two connecting lines therebetween, each station comprising means to transmit electrical impulses over said lines, means to step-up said electrical impulses, relays to receive said impulses, means dependent on said relays to selectively connect one line with the ringing device of one station, means between said one line and said third line to operate the ringing device of the selected station,- and means to disconnect said step-up means when the said impulse transmitting means are inoperative.

18. In a telephone system including connecting lines, stations comprising means to efl'ect electrical impulses in the primary of a transformer, means to intensify said impulses, the secondary of said transformer transmitting said impulses over said lines, means to receive impulses from said lines and selectively connect. one line with a grounded ringing device, grounded means to transmit current over said line to selectively operate said ringing device, means to disconnect the said impulse receiving means of the calling station when its impulse effecting means are operated, and means to dis connect said step-up means when the said impulse etfecting meansare inoperative.

19. In a telephone system including one line and ground, stations comprising means to effect electrical impulses in the primary of a transformer, the secondary of said transformer transmitting said impulses over said line and ground, means to receive impulses from said line and ground and selectively connect said line with a ringing device, a second line for said ringing device,

7 means. to, transmit current over said line and said second line to, operate said ringing device selectively, means to disconnect the said impulse receiving means of the calling station when its impulse effecting means are operated, andmeans to disconnect said stepupv means when the said impulse efiecting means are. inoperative.

2,0, In a telephone system including a plu rality of stations and two connecting lines, therebetween, each 7 station, comprising means to eiiect impulses in the primary of a transformer, the, secondary of said transformer transmitting said impulses over said lines, means to receive impulses from said lines and selectively connect one line with a ringing device, a, third line for said ringing device, meansbetween said one line and said third line to, operate said ringing device of the selected station, means to disconnect the said nnpulse receiv ng means oi the calling .tation when its impulse efliecting means are;

operated, and means to disconnect said stepup means when the, said impulse efi ecting means are inoperative.

In telephone system, stations comprising voice transmitting and receiving me ns, a omb n d pul e sendr a r ceiverhaving electromagnets connected to the, t p qne in s, to thed is ro ated. by the armature of said; electromagnet, means; to; identify stations on said; disc, av qentactmaker op inne by e teeth said. disc; o transmit imp s O r sa d l n s to; dic a e a ec m gnet manua ta operat sa d s mea s depen t on; sa d di c t c nec ne o a d. ines; w th, a r d d ri s ng dev e, and o, ra smit; urre to, op e sai ring ng dei e-v 22- n a t nhQne y tem, st t ns omprising voice transmitting and receiving m ans, a c m n d: imp l e sender and r ceiver having electromagnets connected to one of the main lines, a toothed disc rotated;

by the armature t said electroinagnets,

means tov identify stations on said disc, a contact maker operated by the-teeth of; said disc to transmit impulses over said lines to operate. Said electromagnets, manual means to operate said disc, means dependent on said disc to connect one of said lines with a. ringing; device, a third line for said ringing device, and means to ransmit current to operate said ringing device.

23, In. a telephone system, av selective ringing apparatus consisting: of a disc having a number of teeth equivalent to the capacity of the system, a contact maker operated by the said teeth, manual means to rotate said disc, means including a dial to. indicate the position of said disc with relation to the station pacity 0t the system, a contact maker operated by the said teeth, manual means, to re: tate said disc, meansincludinga disc to indicate the position of said disc with relation to the stations in the system, electromagnets having an armature capable of rotating said disc, a sw tch on said discso as to; connect the ringing device in circuit, a switch dependent on the manipulation of the; said disc to. throw the e ec meg t out of i cui he w ole, connected 0 that e man pulation of. ne i will, ca se ll iscs. in he system to; ore p n ing yta e and c o e th .v ring ng s rcuit of the selected station,

2 n, a elsphcne ystem, a elec iv ringns app us ons st ng- Q d sc h ng a u ber f e -eq iv lent t h capa ty of:

he sy t m, a a el t, ak r Op r ted by the said teeth, manual means to rotate said disc, means including dial, to indicate the po-i sition of, aid d th rela on to e tion in the system, electroma-gnets. having an armature capable of rotating said disc, a switch on said disc so as to connect the ringing device in circuit, a dual switch dependent on the manipulation of the saiddiscto throw the electromagnets out of circuit and connect the said contact maker in the circuit, the whole connected so that the manipulation of one. disc will cause all discs, in the system to correspondingly rotate and close the ringing circuit of the selected station.

26. In a telephone system, a selective ringing apparatus consisting of a disc having a number of teeth equivalent to the capacity of the system, a pointer mounted on, said disc, a dial around said pointer serially numbered up tothe number of teeth on the said disc, a manual operating" shaft slidingly mounted through said disc, means on said shaft to engage said disc when pressed towards the same, a contact maker and breaker mounted so as: to operate by means of said teeth, electromagnets having. an armature and. pawls to engage said teeth, a switch ops erated by the pressing of said shaft to throw the said electromagnets out of circuit and the said contact maker and breaker in circuit, a switch dependent on the position of said pointer to operatively connect the ringing device, the Whole so connected so that the manipulation of one disc will cause the discs of all stations to rotate correspondingly, all pointers pointing at the same number on the dials, and actuate the said pointer dependent switch of the respective station indicated on the dial.

In testimony of the foregoing, I have here unto affixed my signature, this 26th day of September, 1924:, at Merritton, in the Province of Ontario.

JAMES LEO SLATTER'Y. 

